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More Scoop... On The Poop.

Fishing For More Scoop On The Poop?

I warn you now: This is a long post on septic, off grid systems for our zero energy prefab house kit, composting toilets, and... poop.
Here is a great overview on how composting toilets work and why, theoretically, they can reduce 60% of your water use!
From "Becoming UnMoored:"
"Envirolet estimates that composting toilets reduce household water use by 60%.

In fact, Sun-Mar composting toilets estimate that an average family of four flushes 70 gallons of water down the toilet every day, which is a whopping 25,000 gallons per year. They estimate that based on all the composting toilets they’ve sold in the past, their company alone is saving 6,103 gallons of water every minute."
I mentioned earlier the composting toilet for our off grid zero energy passive solar house kit has a drain pipe to deal with possible (Possible! I thought) run off.

From the beginning, our contractor had been talking about a septic field. But I thought, "There must be a better way, if we're separating out black and grey water. It just doesn't seem efficient, the most functional..."
The easy thing to do would be to just get a frickin' septic field.
But it just bothered me: Why get a septic field when if there's nothing but barely-black water (shower & sink), it most likely won't work properly!

I had some great conversations with the Department of Health, and Heather Barber of Topos, LLC.

Our Off Grid Scenario:
We plumbed separately for gray and black water in our off grid, passive solar, prefab house kit.

For black water:
There is the kitchen sink, and the composting toilet (although the composting toilet model we chose is non-electric and self contained, it does indicate a drain pit for run over, i.e. run over only if it exceeds the unit.

I love to cook.
But we compost, and chickens eliminate scrap waste just as many other urban cities and countries embrace in most areas (hellllllllo, Richmond )… hence our “trash” or “waste” is mostly packaging and bones… We prevent solids from going down the kitchen drain, much less won’t install a garbage disposal. So really, the black water in the kitchen will not be overwhelming grossness (my words, not an engineer’s ; ))…

For gray water:
We intend to pipe the gray water downhill using gravity to a fruit orchard that reuses that gray water for irrigation, using an old method that, using gravity, allows water to soak down and turn slowly through the furrows. I keep turning this scenario about in my head, wondering if zoning’s standard septic solution is really the right way to go with this systems plan.

With the black and gray water separated, what is the current, best functioning, yet affordable solution?

Thanks to many helpful people at the Virginia Department of Environmental Quality, I was sent to Marcia Degen of the Health Department who listened patiently to my explanation of our own off grid scenario and site.

Ms. Degen had these comments to add to the green building discussion: (Note: I was typing during /after our discussion so not quoting accurately as much as I would like, she was talking faster than my fingers could type, so if I got anything wrong blame me, not her!)
“Well... You’re not going to have much flow. 
I know it sounds odd, but the smallest standard septic field might be the most cost effective, and  efficient solution for you. Keep it as shallow as possible is a good idea.
There’s also peat you could consider, but your flow would be so infrequent it wouldn’t be wet.”
My Coffee Pot.

I agree about the peat, and explained why I avoid peat – although it’s a common additive / alternative system, peat is neither a local nor renewable resource. Our composting toilet came with a bag of peat – yet lists coffee grounds and sawdust as an alternative, which, for our family, is an abundant, and local resource: We're right down the road from an Amish saw mill! 

(Ok, ok, no coffee carbon footprint comments please…but the reality is that yes, I do go through several gallons of brewed coffee a day…how do you think, honeychile, I make all of this happen? #Caffeine) 

We discussed Boxerwood, a great local example of an alternative waste water treatment system using wetlands. (See also their NEWTS rain garden information here:
(And a random fact about Boxerwood: Did you know the founder of Boxerwood was Sally Mann's dad?)

Ms. Degen confirmed my thoughts on such a system for our own site:
“You wouldn’t have enough water to keep a wetland alive. Boxerwood gets a couple of hundred gallons of waste water daily. Because you separated gray out from black water, it would be such a small amount… Have you considered looking into combining it with your downhill gray water irrigation system? 
The end result might be able to be considered your drain field. You would need to see what your loading rates are, compare your sizing and soil and see… A limitation would be that the field must be 12” under the surface…”
I begin thinking of the natural flash runoff (bad!) gulleys created along our road leading through the property, already there when we bought the land, the planned piping of downhill irrigation systems into an orchard, the softness of the field we plan for the orchard to dig accordingly (which hence, percolates)… we might just actually make all of this work together for good!
“…We do allow drip irrigation so this might be possible. Tying in the toilet overflow drain pipe… IF you do it with a peat system you could do it without energy and just gravity OR, with gravity, have a separate small drainfield, which returns the waste water to ground water.”
I called Heather Barber of Topos, LLC to relay the conversation and she got excited. I asked her to explain those orchard trenches further:
"The furrows would be lined with agricultural tile. As the swales (trenches) are filled with water, you don't want it to drain until water is pushed through the trenches. To prevent soaking we line those areas with tile. Once it gets to the agricultural furrows, then it begins to soak as it passes down the furrows and winds its way amidst the trees."
Topos went to work, and came up with this:
"Conceptual plan for grey/black wastewater re-infiltration at Higher Ground:
Quite similar to the sustainable methods of stormwater infiltration systems, this concept uses the notion of gravity flow and groundwater. The wastewater from the residence would flow through a 6-8” sanitary sewer pipe and outfall into an underground trench downhill from the residence. The residence is currently a 2nd home for a family of 4 thus the waste produced is minimal capacity and a traditional septic system might [be] considered overkill. As would this particular site not be the ideal setting for a wetland outfall system, due to the groundwater levels and the depth at which the trench must be created to take advantage of that.
The concept will be built to feed an allee of fruit trees, as this type of wastewater cannot be used directly on the leaves or fruit of an edible garden. Two trenches 48” x 48” x 68ʼ will be dug and backfilled with a larger aggregate, fine particles screened out, leaving the top 12” grade to be capped with earth. The main trench, is on the downhill side of the residence, the higher grade of the row of fruit trees. A 6” perforated pipe will be centered, 18” below finished grade, in the aggregate trench and follow the natural grade of the trench. The second, lower trench will reside at the lower lateral end of the allee and will be constructed is the same manner as the primary trench. This trench is for overflow purposes in the event of a major rain/natural event. The overflow trench will be connected to the primary trench via a 6”-8” sanitary sewer pipe, at the high side of the primary trench.
The system would take advantage of the underground water table, and when the water table is lower, as in a drought situation, the grey/blackwater will be recharged into the ground and used to provide additional water and nutrient to the fruit tree allee. It also falls within the EPAʼs Title 5 septic treatment guidelines for I/A Technology. 
Similar examples and guidelines include the National Pollutant Discharge Elimination System (NPDES) that falls within the EPA Clean Water Act, has a great example of residential use in Santa Barbara, the EcoHouse in Berkeley, the Harned residence in Idaho designed by Whole Water Systems
Most municipalities have publications that highlight the benefits of using sub-surface infiltration basins, and many companies now manufacture tree well infiltration basins that serve a dual purpose."
Oh, the drama of poop!
Here's some recent articles for Virginia:
FYI, back to composting toilets, here's some items I found very interesting: 
  • Make sure you read Sherman Johnson's comment on the first article I mentioned, "Composting Toilets: All You Ever Wanted To Know," if you are considering installing a composting toilet on your property. In my experience his points are accurate.
  • Here are some favorable and not favorable reviews on a composting toilet page that is a MUST READ: (Keep an open mind and you will get an education!)
    From "The Poop Report": Drawn from extensive comments the article created:

    • I am noting the comment from Tiva, especially regarding dry & wet:
      "...The unit needs to be emptied frequently, and because it's a continuous composter, you always get fresh, uncomposted poop mixed in with the stuff you're trying to get rid of. ... The rake bar usually gets stuck, so you can't use the nifty emptying tray, and instead you need to empty the unit with a trowel, mixing fresh poop in with your composted poop. I have a PhD in ecology, and I've been composting out in the garden for 20 years. But I still find this toilet incredibly fussy. Either it gets too dry, and the poop turns into rocks and stops composting, or else it gets too wet, and turns anaerobic. Toilet paper doesn't break down. On and on. Don't get me wrong--I'm all for composting toilets. But get a remote model! And get a batch model, so that your poop can compost separately before you empty the unit. Continuous, compact models don't work." Oy!
    • From poopmachineowner:
      " I searched this site out to rant about my frustration regarding the Envirolet remote low water composting system I own. Besides of venting my exasparation, I learned a whole lot from this site. The Humanure Handbook was very helpful understanding the composting process.What I learned from it led me to start using my envirolet system differently, and I must say, with success. It is a valuable reading, and I am not going to go into details, but what I found was that the Envirolet instructions (rather casually) mentions to add a quarter of a cup of peat moss (the carbon part of the composting) per person per day to the composter. It is way too inadaquate for the composting to occur.

      Now, The Humanure Handbook is not very practical regarding the exact quantity of carbon (wood shavings, etc) to be added, so I started to add 3 palmful of sawdust per day. Voila,the smell is gone, and after 5 weeks a lot of composting has happened.
       How do I know? Because the composter is filling up at an alarming rate, so today I had to empty it. With the one inch drain line and the sawdust the fluid buildup is not there any more. So, now it seems the composting is happening, but the unit is not large enough to process the whole load, before it has to be emptied. And I am alone in this house...Peat moss doesn't do the job, maybe we produce a different set of bacteria here.... I guess now I have to start reducing the carbon somewhat, and see the results. Summerising, I still do not think very highly about Envirolet, one shouldn't have to go through all that frustrations after doling out $2000, and having to experiment with poop for years to come. In the age of microprocessors I would imagine some company will come up with a smart composter, monitoring the conditions, add the necessary carbon, etc. maybe even empty into a separate container,and test their product extensively, before market it with a permanent Sale offer."
    • Poopin Terry is talking about a Biolet, but I found this informative:
      "When using this toilet, the most important factor is the temperature setting. If it is too low, there will be liquid build up and odor. You can also pop the shear pin off as the stirring arm can't move through the heavy wet compost. If it is too high, the material will dry out before it can break down. In the early months I even added a bit of water now and then as I played with the heat settings. The best way to find the mark is to set it a bit low until you see liquid show up in the tube on the side, then increase one point each day until the liquid disappears. that should be the right spot. "

      I will be bringing a spray bottle with water out to check out this poop situation more closely.
    • From MaineGirl: "One of the more interesting aspects of the set-up this year was using silicon caulking around the middle seam of the unit. The fans were running when we started putting the goo on, and when the caulking reached all the way around the unit to close the loop, the fans started making a different pitched hum-- we're hoping it's actually air-tight now in the box, and the only air into the system comes from the down draft through the toilet. We'll see... I'm not expecting miracles, but it would be nice if the unit didn't ooze out ickiness."

      "...So, again, we're giving the Envirolet another try-- I put hay in the bottom instead of the ridiculous tissue paper that the company recommends, and I'm going to increase the peat/person ratio. I guess we'll let you know how it goes after the Fourth of July Weekend."
    • From Pavel Up North:
      "...2. the raking bar must be vigorously agitated every day for a couple of minutes. (Copeland's note: I do this, I assume you mean the top *aerating* bar though!) The bars are not very effective and will not work at all if the compost dries out - becomes like concrete, requiring full disassembly of the unit (top removed not just the front hatch opened) so that it can be upturned and the 'stones' pried out. (Copeland's note: Boy will I be keeping vigilant on this!) 3. any build up of toilet paper around the sides of the 'mass' must be removed weekly. I use a 3 foot "grabber' with pistol grip control 4 Lots and lots of peat moss, sawdust/chips should be added. Make sure the toilet paper is designed for composting not flushing. 5 A spray bottle with Simple Green Cleaner (pH about 9.5) should be liberally used. This cleans the bowl/trap door and partially neutralises the acidic pee. ... 7 Clearly the unit only works properly when an equilibrium is established involving moisture, pH, amount of poop, carbon (paper/peat etc.) and temperature."
    • Chris in TN : "I have an Envirolet low water remote system with two sealand toilets connected. It has worked just fine over the four or five years I have had it. You do have to replace the fans and heaters every few years if you run them as much as I do."
    • Again from MaineGirl: "...someone who has an Envirolet and has has retrofitted it to work as best it can. Here's a link:"
Copeland's note: I appreciate Tiva and MaineGirl in this thread. These gals are INDUSTRIOUS and determined, and keep coming back and reporting, year after year. They would SO be invited to my Girls Nite if they lived near. ***Make sure you scroll alllllllllll the way down to the bottom of the page to see what Tiva does in the end. Not that I recommend doing that. But she's determined! ***

On my end I will be taking a fresh look at composition, temperature, making sure no upper masses harden.  What also interests me are the comments on toilet paper, maybe I will ask people to instead dispose of toilet paper into a trash can if it becomes an issue.

Read on HUMANURE and its history here:

If composting toilets interest you, don't you DARE leave this blog post without perusing The Humanure Handbook
Of course I knew about The Humanure Handbook when researching composting toilets, but I wish I had read it before making the composting toilet purchase three years ago, with a then-3 and then-5 year old whining and pulling on me, not able to read the fine print, when trying to find a point-and-click "easy solution" (AND, Handsome Husband's Christmas Present! Yes, this was his Christmas present three years ago. Got him back for that year he gave me car parts, eh?) for our off grid house.

This is NOT to say our composting toilet experience is bad. I am looking forward to the next years. But it is clear a purchaser needs education, and that these "click and buy" toilet websites approach it as "Buy the toilet today, and it's your responsibility to know all this down the road."  

Even my composting starter mix, which arrived today, "free" thanks to a tweet about toilets a few weeks ago, arrived with a bag, a paper mat, and no instructions! I understand (and practice) Save-A-Tree-Don't-Print-A-Bunch-Of-Paper-But-Keep-Info-On-The-Internet.  But you would think they'd at least print, "Go here for instructions - http://(WherePeopleCanReadInstructionsOnTheToilet)" on the soil packaging!

To be fair, Envirolet has done a great job creating short, easy to see and understand videos.
Here's one in particular I'll be using very soon: 

Here's one I *wish* Handsome Husband had seen, or at least read the manual (I did!) before curiously pulling the rake bar, not the aerator:

And don't fergit to finish correctly whatchoo start:

Regardless of the system, it is clear composting toilets have real issues that need to be addressed / users need to be educated in, preferably before the purchase.  More informed purchasers make happier customers. It's clear composition, mixture, aeration, and temperature are critical to a successful experience!  

So, out of curiosity, NEXT WEEKEND?
I'mma gonna empty our composting toilet and get up close and personal-like with the scoop... on the poop. Or... maybe I won't. WE'LL SEE.

And I see a possible second composting outdoor bin in our future... we... shall... see.
More on rudimentary composting here

Here's another gem I picked up from reading these forums and web sites: 
Until now, at Higher Ground, I have been guiltily discarding the few kitchen scraps I incur while there. (To prevent such waste, I was making the food in Richmond, giving our chickens there the scraps as usual. But every time I cut a vegetable but don't want to throw it outside in case it somehow attracts wildlife for the wrong reasons, I feel horrible - literally, throwing that in a trash can, even for safety's sake, is a WASTE!)

From EnviroletBuzz:
The composting toilet possesses the ability to recycle much of your household waste. Food scraps, paper, lawn clippings and grease from you grease traps and greywater systems can be composted back through the toilet. If you choose to put in a reed bed greywater systems, the annual clippings can also be composted. There is no wastage in this system."

Wow. So from now on, those vegetable scraps get tossed into the toilet until we live there permanently and have chickens. Try doing that in your average toilet!!!

And with that, I'm off to bed.
I can't believe I just spent my Friday night researching composting toilets more and writing about poop!

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At 11/12/10, 8:06 PM , Anonymous Nancy Heltman said...

I am no expert but we just put in a septic system at Shenandoah River State Park that uses poop eating bugs. As a result we have to keep the campground open year round because without enough poop the bugs will die. I'm thinking of posters for the bath houses with "Feed me" signs.

At 11/12/10, 8:51 PM , Blogger Passive Solar Prefab Homes said...

[How do I "like" this comment? : ) ]


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